Centrifugal combustion method using air-flow in a furnace

ABSTRACT

This invention, Centrifugal and Divided Space combustion method, need to install a cylindrical fuel pot, the first combustion chamber, the second combustion chamber and an exhaust pot. It also needs to install the upper and the lower pots outside the first combustion chamber and the fuel pot in order to have the lower and the upper air paths inside the outer pots. One or several ventilator(s) to make air-flow is tangentially connected to the upper and the lower air paths at the lower part of the upper outer pot. And several air-flow control devices should be located at the upper part of the upper air path. Thus, the invention is composed to realize the complete combustion only with the air supply into the furnace. In this case, the space in the furnace is divided into many combustive sectors by the air-flow.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates, in general, to a centrifugal combustionmethod using air-flow in a furnace and, in particular, to a centrifugalcombustion method using air-flow in a furnace, in which combustiblessuch as low-calorie wastes with high moisture content, high-calorieplastics and rubbers with low moisture content, and high-calorie wasteliquid are completely and rapidly combusted at high temperature by onlysupplying air into the furnace without auxiliary devices and fuel whilea space in the furnace is divided into many combustive sectors byair-flows due to a centrifugal force of air under high pressure rapidlysupplied to the furnace and revolved in high speed in the furnace.

2. Description of the Related Art

A conventional method for combusting wastes or waste oil, comprises thesteps of supplying combustibles into a combustion chamber in a furnace;igniting combustibles in the combustion chamber with the use of anignition burner; combusting combustibles with cool air directly suppliedto an upper, a mid, and a lower part of the combustion chamber.

However, the conventional method has disadvantages in that high-calorie,low-calorie, and wet wastes are incompletely combusted, and combustionefficiency is low because wastes are combusted with only cool airsupplied through a ventilator. Incompletely combusted combustiblesremain or end up in a landfill, and so resources are wasted and anenvironment is polluted. In addition, incomplete combustion ofcombustibles causes various toxic substances fatal to humans, such asdioxin as well as carbon dust to be emitted into the atmosphere, and theburner is continuously operated and auxiliary fuel (e.g. diesel fuel) isadditionally used because incompletely combusted remains should be againcombusted, thereby the cost of fuel is high, combustion time is long,and combustion efficiency is lowered.

Furthermore, other disadvantages of the conventional method are that aspecial burner capable of being used at high temperatures is needed, airis supplied to the furnace under high pressure, and refractory bricksshould be constructed inside of the furnace because combustibles arecombusted at high temperature, and so combustion cost becomes high.Particularly, a combustion chamber made of metals does not endure hightemperatures and thus the chamber is eroded, thereby durability of thefurnace is reduced.

SUMMARY OF THE INVENTION

Accordingly, the present invention has been made keeping in mind theabove problems occurring in the prior art, and an object of the presentinvention is to provide a centrifugal combustion method in whichcombustibles are completely combusted at 1500 to 1900° C. by aircirculation without any additional device or catalyst.

Another object of the present invention is to provide a centrifugalcombustion method, in which low-calorie fuel is sufficiently combustedwithout auxiliary fuel and about 100% of heat produced during combustionof the low-calorie fuel is utilized.

It is still another object of the present invention to provide acentrifugal combustion method, in which high-calorie fuel issufficiently combusted without auxiliary fuel and about 100% of heatproduced during combustion of the high-calorie fuel is utilized.

It is yet another object of the present invention to provide acentrifugal combustion method, in which wet fuel or waste containing ahumidity of 100% or less is sufficiently combusted without auxiliaryfuel and heat produced during combustion of the wet fuel or wastecontaining a humidity of 100% or less is sufficiently utilized.

It is a further object of the present invention to provide a centrifugalcombustion method, in which combustibles are completely combusted in thesame size combustion chamber as a conventional furnace (incinerator) ata speed several times quicker than a conventional combustion method.

Based on the present invention, the above objects can be accomplished byprovision of a furnace comprising a cylindrical fuel tank; a cylindricalfirst combustion chamber; a cylindrical second combustion chamber; acylindrical exhaust tub; an upper and a lower outer tub wrapping thefirst combustion chamber and the fuel tank such that spaces are formedbetween the upper outer tub and the first combustion chamber, andbetween the lower outer tub and the fuel tank; one or severalventilator(s) connected to a lower part of the upper outer tub such thatthe ventilator is tangentially communicated with a space between, thefirst combustion chamber and the upper outer tub, and to an upper partof the lower outer tub through air connection pipe(s) such that theventilator is tangentially communicated with a space between the fueltank and the lower outer tub; a plurality of air-flow control devicespositioned at an upper part of the space between the first combustionchamber and the upper outer tub.

In the furnace, combustibles are completely and rapidly combusted athigh temperature while a space in the furnace is divided into manycombustive sectors by air-flows owing to a centrifugal force of airunder high pressure rapidly supplied to the furnace and revolved at highspeed in the furnace.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features and other advantages of thepresent invention will be more clearly understood from the followingdetailed description taken in conjunction with the accompanyingdrawings, in which:

FIG. 1 is a longitudinal sectional view of a furnace according to thepresent invention, with an air-flow inside of the furnace being shown;

FIG. 2 a is a transverse sectional view of the furnace taken along theline A—A of FIG. 1, with the air-flow inside of the furnace being shown;

FIG. 2 b is a transverse sectional view of the furnace taken along theline B—B of FIG. 1, with the air-flow inside of the furnace being shown;

FIG. 2 c is a transverse sectional view of the furnace taken along theline C—C of FIG. 1, with the air-flow inside of the furnace being shown;

FIG. 2 d is a transverse sectional view of the furnace taken along theline D—D of FIG. 1, with the air-flow inside of the furnace being shown;

FIG. 3 is a longitudinal sectional view of the furnace according to thepresent invention, with a plurality of combustive-sectors divided by theair-flow being shown;

FIG. 4 a is a longitudinal sectional view of the furnace with thepre-heated air-flow in a and g parts of the furnace being shown;

FIG. 4 b is a longitudinal sectional view of a portion of the furnacewith the pre-heated air-flow in b part of the furnace being shown;

FIG. 4 c is a longitudinal sectional view of a portion of the furnacewith an exhaust air-flow in c and f parts of the furnace being shown;

FIG. 4 d is a longitudinal sectional view of a portion of the furnacewith the exhaust air-flow in d part of the furnace being shown; and

FIG. 4 e is a longitudinal sectional view of a portion of the furnacewith the exhaust air-flow in e part of the furnace being shown.

DETAILED DESCRIPTION OF THE INVENTION

Reference should now be made to the drawings, in which the samereference numerals are used throughout the different drawings todesignate the same components.

In order to accomplish a centrifugal combustion method according to thepresent invention, provided is a furnace 50, comprising a flange 2positioned around a lower part of a cylindrical first combustion chamber1 and outwardly protruded from the first combustion chamber 1; an upperand a lower outer tub 3 and 4 firmly set over and under the flange 2,respectively; a fuel tank 6 positioned under the first combustionchamber 1, while an upper side of the fuel tank 6 being opened and inclose contact with a bottom of the flange 2 of the first combustionchamber 1, and a lower side of the fuel tank 6 being combined with ahydraulic jack 5 for attaching/detaching the fuel tank 6; a flange 9outwardly protruded from a lower part of a second combustion chamber 8having an exhaust tub 7 positioned on an upper side thereof, andpositioned on an upper part of the upper outer tub 3; one or pluralventilator(s) 11 connected to an air supply pipe 10 which istangentially connected to the lower part of the upper outer tub 3, andconnected through an air connection pipe 13 to an air suction pipe 12which is connected to the upper part of the lower outer tub 4 such thatthe ventilator 11 is communicated with the air suction pipe 12; an airdirection control plate 14 positioned on an upper part of a spacebetween the first combustion chamber 1 and the upper outer tub 3, andpositioned at the upper part. of the upper outer tub 3; and a pluralityof air-flow control devices 16 positioned at the upper part of the upperouter tub 3, and each consisting of an air direction control plate 14and a control rod 15 rotatably combined with the air direction controlplate.

In addition, the furnace 50 according to the present invention comprisesan opening/shutting door positioned at the lower outer tub 4 coveringthe fuel tank 6, through which entrance and exit of the fuel tank 6 isallowed, and a plurality of rollers firmly set on a bottom of the fueltank 6 for transporting the fuel tank 6 by use of rails, even though theopening/shutting door and rollers are not shown in drawings.

According to the present invention, a centrifugal combustion methodusing air-flow in a furnace, comprises the steps of firstly preheatingcool air by absorbing a caloric heat from an exterior wall of a fueltank 6, and therefore, cooling the wall of the fuel tank 6, in whichventilator noise is reduced by sucking the cool air through a spacebetween the fuel tank 6 and a lower outer tub 4; supplying the firstlypreheated air into a space formed between a first combustion chamber 1and an upper outer tub 3 through a ventilator 11 which is tangentiallyconnected to a lower part of the lower outer tub 4 to make the suppliedair ascend and revolve in the space formed between a first combustionchamber 1 and an upper outer tub 3, in which the firstly preheated airabsorbs a caloric heat of the first combustion chamber 1 andsimultaneously cools the exterior wall of the first combustion chamber 1while ascending and revolving at high speed; controlling the amount ofthe secondly preheated air which ceases to ascend because a flange 9positioned at a lower part of the second combustion chamber 8 obstructsthe ascending of the secondly preheated air by controlling the angle ofan air-flow control device 16; thirdly preheating the secondly preheatedair supplied into the first combustion chamber, in which the secondlypreheated air descends down to the fuel tank with revolving in contactwith an interior wall of the first combustion chamber 1 due to thecentrifugal force caused by the revolution of the air-flow which iscontinued still in the first combustion chamber, absorbs caloric heatfrom the interior wall of the first combustion chamber and thereforecools the interior walls of the first combustion chamber 1 and the fueltank 6.

By taking the steps mentioned in the above, the thirdly preheated air ismixed with fuel in the fuel tank 6 forming a mixed ignition combustivesector f, and the resulting mixture revolves and is combusted therein.High gravity combustibles incompletely combusted in the mixed ignitioncombustive section f are swept into the thirdly preheated air b which isdescending down in the first combustion chamber 1 forming a high gravitycombustive sector c, in which they are combusted in a sufficiently longcombustion distance and a lengthy period of combustion time. Low gravitycombustibles incompletely combusted in the high combustive sector c aretransferred into a center of the first combustion chamber 1 forming alow gravity high temperature combustive sector d, in which they arecollected, combusted more and ascend to the second combustion chamber 8while revolving and being combusted. A high temperature heat core sectore is formed at the center of the furnace, the temperature of which ismaximized in the furnace.

Incompletely combusted combustibles in the low gravity high temperaturecombustive sector d and the high temperature heat core sector e areswept again into the descending and revolving thirdly preheated air b inthe first combustion chamber 1 due to their high gravity and thecentrifugal force of the revolving air-flow, and therefore suppliedagain into the low gravity high temperature combustive sector d or thehigh temperature heat core sector e together with the thirdly preheatedair b.

Some combustibles incompletely combusted in the first combustion chamber1 and transferred to the second combustion chamber 8 with the air-flowascending up from the central parts of the first combustion chamber 1are combusted again by the secondly preheated air a ascending throughthe air-flow control device 16. The secondly preheated air absorbs acaloric heat from the interior wall of the second combustion chamber 8,and therefore cools the wall. Finally, according to this invention, onlycombustion gas, namely the combustibles completely combusted are emittedthrough an exhaust tub 7.

The furnace 50 is operated, as follows.

After fuel 17 filled in the fuel tank 6 is ignited by a hand orautomatic ignition device, an upper side of the fuel tank 6 is closelyattached to a bottom of the flange 2 positioned at a lower part of thefirst combustion chamber 1 through a hydraulic jack 5 forattaching/detaching the fuel tank 6. Next, a caloric heat is producedduring mixing of fuel with air and combusting of the resulting mixturein the fuel tank 6, and the exterior wall of the fuel tank 6 is cooledand cool air 5 supplied through a bottom of the lower outer tub 4 isfirstly preheated while the cool air flows through a space between thefuel tank 6 and the lower outer tub 4, by operating the ventilator 11 athigh speed. The firstly preheated air g is tangentially supplied throughthe ventilator 11 into a space between the first combustion chamber 1and the upper outer tub 3 and ascends by revolving at high speed. Atthis time, firstly preheated air g supplied by the ventilator 11 absorbsthe caloric heat of the first combustion chamber 1 to be changed into asecondly preheated high temperature air a, as well as cools an exteriorwall of the first combustion chamber 1. When air ascending by revolvingin a space between the first combustion chamber 1 and the upper outertub 3 reaches a bottom of the flange 9 of the second combustion chamber8, the air does not ascend any more because the flange 9 obstructsascending of the air, and the amount of air supplied into the firstcombustion chamber 1 and the second combustion chamber 8 can becontrolled by an angle of an air direction control plate 14, which ispositioned under the flange 9 of the second combustion chamber 8,changed with rotation of control rods 15 of air-flow control devices 16.

Because polymer based high-calorie wastes such as waste vinyl, wasteplastic, and waste tires have many volatile components and rapidlydecompose, when the polymer based high-calorie wastes are in contactwith high temperature air, a temperature of combustibles is increasedand thus sooty smoke is produced due to an incomplete combustion, inconjunction with an explosive combustion. At this time, if the airdirection control plate 14 of the air-flow control device 16 is, forexample, at an angle of 135° with a revolution direction of air (asshown in drawings), the amount of secondly preheated high temperatureair a descending to the first combustion chamber 1 is reduced and acombustion rate becomes slow, thereby preventing the explosivecombustion. In addition, substances incompletely combusted in the firstcombustion chamber 1 are completely combusted with secondly preheatedsufficiently high temperature air by increasing the amount of airsupplied into the second combustion chamber 8.

On the other hand, when the air direction control plate 14 of theair-flow control device 16 is, for example, at an angle of 45° with arevolution direction of air, the amount of air supplied to the firstcombustion chamber 1 is increased and the amount of air supplied to thesecond combustion chamber 8 is decreased. In other words, a combustionrate, a combustion temperature, and a required heat capacity per hourcan be controlled by the air-flow control device 16.

Air supplied to the first combustion chamber 1 is not diffused to acenter of the first combustion chamber 1 because of the centrifugalforce which is due to a continuous revolution of air, but descends intothe fuel tank 6 storing fuel 17 while revolving in close contact withthe interior wall of the first combustion chamber 1. At this time, theair supplied to the first combustion chamber 1 cools the interior wallof the first combustion chamber 1, which is heated by radiation heatfrom the high gravity combustive sector c, the low gravity hightemperature combustive sector d, and the high temperature heat coresector in the first combustion chamber 1, and is simultaneously changedinto the thirdly preheated high temperature air b.

Thirdly preheated high temperature air b supplied to the fuel tank 6 isrevolved at high speed and mixed with fuel 17, the resulting mixture isthen combusted in the mixed ignition combustive sector f before it istransferred to a center of the first combustion chamber 1. At this time,high temperature atoms or molecules are transferred to the low gravityhigh temperature combustive sector d and high temperature heat coresector 2 which is a maximum temperature in the first combustion chamber1, and ascend while revolving in high temperature and high speed,thereby the mixture of the thirdly preheated air b with fuel 17 iscompletely combusted.

Additionally, high gravity combustibles are transferred to the highgravity combustible sector c closer to the center of the firstcombustion chamber 1 than thirdly preheated air-flow b, revolves in highspeed at high temperature, and are combusted while securing asufficiently long combustion distance and time. Combusted combustiblesbecome greatly reduced in gravity to the extent of approaching zero, andare transferred to the low gravity high temperature combustive sector dand the high temperature heat core sector e to be completely combustedat high speed and at high temperature.

Meanwhile, combustibles not thermally decomposed in the low gravity hightemperature combustive sector d and the high temperature heat coresector e. descend due to the weight of the combustible, and aretransferred to the thirdly preheated air-flows b and again combusted,thereby the combustible is completely combusted.

Remains incompletely combusted in the first combustion chamber 1 arecompletely combusted with secondly preheated high temperature air-flow aascending through the air-flow control device 16 in the secondcombustion. chamber 8, which simultaneously cools the interior wall ofthe second combustion chamber 8, thus nonpolluting combustion gas isemitted through an exhaust tub 7.

Furthermore, because the lower outer tub 4 is positioned outside of thefuel tank 6 in such a way that a space is formed between the fuel tank 6and the lower outer tub 4, cool air sucked by the ventilator 11 andpassing through the space between the fuel tank 6 and the lower outertub 4 cools the exterior wall of the fuel tank 6, and simultaneouslyabsorbs the caloric heat of the fuel tank 6 to be preheated. Inaddition, because the space between the fuel tank 6 and the lower outertub 4 acts as a suction path, and the cool air passing through the spaceis firstly preheated before being supplied into the ventilator 11, noisefrom the ventilator 11 is reduced, in comparison with the conventionalventilator which sucks cool air directly from the atmosphere.

After polymer based high-calorie wastes such as waste vinyl, wasteplastic, waste tires, and waste oil was incinerated according to thecentrifugal combustion method of the present invention, a temperaturedistribution in the furnace 50 was measured to be 100 to 200° C. in thesecondly preheated air a, 300 to 500° C. in the thirdly preheated air b,1000 to 1200° C. in the mixed ignition combustive sector f, 1200 to1400° C. in the high gravity combustive sector c, 1300 to 1500° C. inthe low gravity high temperature combustive sector d, and 1500 to 1900°C. in the high temperature heat core sector e.

Therefore, the present invention provides a centrifugal combustionmethod, characterized in that toxic substances fatal to humans such asdioxins are completely decomposed at high temperature and onlynonpolluting gas is emitted to the atmosphere because only combustiongas of 1300° C. or higher thermally decomposed in the low gravity hightemperature combustive sector d and the high temperature heat coresector e is emitted.

INDUSTRIAL APPLICABILITY

As described above, the present invention provides a centrifugalcombustion method, in which combustibles can be completely combusted athigh temperature by supplying air through a ventilator into a furnacewithout any separate auxiliary device or auxiliary fuel and by dividinga space in the furnace into many combustive sectors with the use of acentrifugal force due to high speed revolution of air. The centrifugalcombustion method of the present invention has advantages in thatalthough materials of the furnace are not special refractory materialsbut metals, the furnace can be durably used without a conventionalspecial burner capable of enduring high speed and temperaturecombustion, supplying of oxygen under high pressure, and a firebrickused to protect the wall of the furnace because a caloric heat isabsorbed by preheated air-flow revolving in high speed around aninterior and an exterior wall of a first combustion chamber, and aroundinterior walls of a fuel tank and a second combustion chamber and thusexcessive of heating of the fuel, the first and the second combustionchamber, and the upper and the lower outer tub are prevented.

Other advantages of the present invention are that size and weight ofthe furnace according to the present invention are reduced by two timesor more in comparison with a conventional furnace because a structure issimple and a high temperature and high speed combustion is realized,inflammable substances not usually suitable for incineration can berapidly incinerated, a boiler used in a vinyl house or bathhousereutilizes a complete combustion heat in order to save energy, andconstruction and operational costs of a sanitary landfill are savedbecause completely combusted gas is emitted from the incinerationfurnace in order to avoid polluting an environment.

The present invention has been described in an illustrative manner, andit is to be understood that the terminology used is intended to be inthe nature of description rather than of limitation. Many modificationsand variations of the present invention are possible in light of theabove teachings. Therefore, it is to be understood that within the scopeof the appended claims, the invention may be practiced otherwise than asspecifically described.

1. A centrifugal combustion method using air-flow in a furnace,comprising the steps of: supplying air to a space formed between a firstcombustion chamber positioned at an upper part of a fuel tank and anouter tub wrapping said first combustion chamber through one or moreventilators tangentially connected to a lower part of said outer tubsuch that the air supplied through said ventilators is preheated andascended with revolving inside of said space formed between said firstcombustion chamber and said outer tub; and, controlling the direction ofthe air-flow that ascended to the top of said space formed between saidfirst combustion chamber and said outer tub so that the necessary amountof air descends inside of said first combustion chamber with revolvingin contact with an interior wall of said first combustion chamber, andthe remaining part of said air further ascends inside of a secondcombustion chamber located at an upper part of said first combustionchamber with revolving in contact with an interior wall of said secondcombustion chamber, the revolving of said air in contact with saidinterior walls of said combustion chambers being accomplished by thecontinuous supply of the air by said ventilators.
 2. The methodaccording to claim 1, further comprising the step of preheating the airin a space formed between said fuel tank and a lower outer tub wrappingsaid fuel tank before being supplied into the space formed between saidfirst combustion chamber and said outer tub through said ventilators. 3.The method according to claim 1, further comprising the step ofcontrolling a combustion rate, a combustion temperature, and a requiredheat capacity per hour with said air-flow control devices that comprisean air direction control plate positioned at the upper part of the spacebetween the first combustion chamber and the outer tub, and a controlrod rotatably combined with said air direction control plate.
 4. Acentrifugal combustion furnace using air-flow comprising: a cylindricalfirst combustion chamber; a cylindrical second combustion chamberpositioned over said first combustion chamber; a cylindrical exhaust tubpositioned over said second combustion chamber; a fuel tank positionedunder the first combustion chamber; an outer tub wrapping said firstcombustion chamber such that a space is formed between said outer andsaid first combustion chamber; one or more ventilators tangentiallyconnected to a lower part of said outer tub such that the air suppliedby said ventilators ascends with revolving in the space formed betweensaid first combustion chamber and said outer tub; and one or moreair-flow control devices positioned at an upper part of said space tocontrol the direction of the ascended air-flow; a lower outer tubwrapping said fuel tank such that a space is formed between said lowerouter tub and said fuel tank; a flange positioned outwardly around thelower part of said first combustion chamber dividing the space formedbetween said outer tub and said first combustion chamber and the spaceformed between said lower outer tub and said fuel tank; and one or moreair pipes connecting said ventilators and the space formed between saidlower outer tub and said fuel tank.